Lead concentrations (mg/Kg) in soil samples at a reference area and a cleanup area. Nondetects reported as <39. There are 14 observations for each area.

EPA.94b.lead.df

Format

A data frame with 28 observations on the following 4 variables.

Lead.orig

a character vector of original lead concentrations (mg/Kg)

Lead

a numeric vector of lead concentrations with <39 coded as 39

Censored

a logical vector indicating which observations are censored

Area

a factor indicating the area (cleanup vs. reference)

Source

USEPA. (1994b). Statistical Methods for Evaluating the Attainment of Cleanup Standards, Volume 3: Reference-Based Standards for Soils and Solid Media. EPA/230-R-94-004. Office of Policy, Planning, and Evaluation, U.S. Environmental Protection Agency, Washington, D.C. pp.6.20–6.21.